Shen Hui, Shen Xinnan, Wang Ruozhong, Wu Min
Department of Nutrition and Food Hygiene, School of Public Health, Fudan University, Key Laboratory of Public Health Safety, Ministry of Education, Shanghai 200032, China.
Wei Sheng Yan Jiu. 2011 Nov;40(6):684-7.
To study the protective effect of theanine on cerebral ischemia-reperfusion injury induced by focal cerebral ischemia in rats.
Sprague-Dawley rats were randomly assigned into five groups: model group, shame (SH) control group and 3 theanine groups (Th-L,Th-M and Th-H). The rats in model and SH groups were given distilled water, and the rats in Th groups were given theanine solution (10, 30 and 90 mg/kg respectively) intragastrically for 15 days. Then the cerebral ischemia-reperfusion injury was established by middle cerebral artery occlusion (MCAO) in the model and Th groups, and SH group was used as a fake surgery control. The score of neurological behavior was evaluated at the 3rd and 24th hours after reperfusion. Rats were sacrificed at 24h after reperfusion, and the brain index was measured. The concentrations of aspartic acid (Asp), glutamic acid (Glu), glycine (Gly), gamma-aminobutyricacid (GABA) and theanine (The) in rat brain following ischemia-reperfusion were determined. The expressions of BDNF mRNA and Bcl-2 mRNA in hippocampi were examined by reverse transcription polymerase chain reaction (RT-PCR) technique.
Compared with model control group, the neurological deficits of theanine treated groups were milder; and the symptoms were more gently. The concentration of neurotransmitter Asp was lower while the Gly and GABA were higher, and a trend of dose-effect relation was existed. The expressions of BDNF mRNA and Bcl-2 mRNA in hippocampi were up-regulated in the theanine treated groups compared with model group (P < 0.05).
Theanine has a protective effect on cerebral ischemia-reperfusion injury in rats, which may be associated with its interaction with amino acid neurotransmitters and up-regulating the expression of BDNF mRNA and Bcl-2 mRNA.
研究茶氨酸对大鼠局灶性脑缺血所致脑缺血-再灌注损伤的保护作用。
将Sprague-Dawley大鼠随机分为五组：模型组、假手术（SH）对照组和3个茶氨酸组（低剂量茶氨酸组、中剂量茶氨酸组和高剂量茶氨酸组）。模型组和SH组大鼠给予蒸馏水，茶氨酸组大鼠分别给予茶氨酸溶液（10、30和90mg/kg）灌胃15天。然后，模型组和茶氨酸组通过大脑中动脉闭塞（MCAO）建立脑缺血-再灌注损伤，SH组作为假手术对照。在再灌注后第3小时和第24小时评估神经行为评分。再灌注24小时后处死大鼠，测量脑指数。测定缺血-再灌注后大鼠脑内天冬氨酸（Asp）、谷氨酸（Glu）、甘氨酸（Gly）、γ-氨基丁酸（GABA）和茶氨酸（The）的浓度。采用逆转录聚合酶链反应（RT-PCR）技术检测海马中脑源性神经营养因子（BDNF）mRNA和Bcl-2 mRNA的表达。
与模型对照组相比，茶氨酸处理组的神经功能缺损较轻，症状较缓和。神经递质Asp浓度降低，而Gly和GABA浓度升高，且存在剂量-效应关系趋势。与模型组相比，茶氨酸处理组海马中BDNF mRNA和Bcl-2 mRNA的表达上调（P<0.05）。
茶氨酸对大鼠脑缺血-再灌注损伤具有保护作用，其机制可能与其对氨基酸类神经递质的影响及上调BDNF mRNA和Bcl-2 mRNA的表达有关。
